Recently I was working on a bread board circuit provided by jc2048 . One of the things that I find very convenient when wiring up a bread board are short wires with an alligator clip on one end and a bread board pin on the other. I use these cables to hook up peripheral meters, sensors, and actuators to the bread board circuit. In the past I have taken cheap alligator to alligator jumper cables, cut them in half and just added a bread board pin to the cut end. While this works the cables do not turn out to be long term durable or dependable. For one thing the wires of these cables are seldom soldered to the alligator clip. Instead the copper wire (what little there is) is folded back alongside the outer insulation and then the alligator clip is crimped down on the wire and the insulation. I have taken brand new jumper cable made like this and had resistance readings of 1 Ohm from alligator to alligator.

 

After fighting with my old patch wires on this last bread board I decided to take the time and make up some that would be of better quality and more durable. I began the project with a bag of the same old cheap jumper cables.

 

 

This would be the source of Alligator clips and covers for the new Bread Board Clips. I will be using special wire that I have salvaged from dental handpiece cords for the wire in the new BB patch cables. This wires has an overall small diameter but has an over sized multi strand conductor. One day I took the time to count the strands on one of these type of wires and there was over a hundred strands. This many strands makes the wire very flexible and the over all gauge allows the wire to carry a reasonable current. In the dental application this type of wire will often carry 2 or 3 amps. Here is a picture of the original jumper cable wire along side one of the special wires.

 

 

The alligator clips that I had salvaged from the cheap jumper cables were next soldered to the high strand wire and the crimp at the back of the alligator clip was used as intended to provide a strain relief on the wire. As much as possible I try to use matching colors in the construction of the BB clips. At 70 there are enough things to confuse me when I build without any color confusion.

 

For the pin end of the cables I will take standard square pin, breakable, male headers and add them to the free end of the wire. The solder is covered with a short piece of heat shrink which serves as an insulator and also a strain relief so that the wire is not stressed at the solder joint.

 

Here is what the bag of jumper cables has turned into:

 

  

 

With the new alligator patch cables in hand I set up the experiment that had inspired me to make them.

 

 

The flexibility of the cables make it easy to set up and position. My old cables were constantly applying torque to the circuit board in one direction or another making it difficult to get things to stay where I wanted them. The net out of pocket cost of this project was under $3.

 

John